Tremendous research efforts have been directed to a perpendicular magnetic recording system for a long time as a system which can carry out recording with higher density as compared with a system that carries out magnetic recording in the longitudinal direction (in the in-plane direction) (longitudinal magnetic recording system). In order to achieve a next-generation magnetic recording technique that enables a recording density exceeding 10 Gb/in.sup.2, various studies and developing efforts have been directed to designs and machining processes for heads and media having constructions that unitize features of the perpendicular magnetic recording system. In particular, with respect to magnetic heads used for perpendicular magnetic recording/reproducing processes, studies have been directed to a single magnetic pole head which has an optimal construction.
Along with the recent developments in the technique for achieving higher density in the longitudinal magnetic recording system, a method in which the thickness of the main magnetic pole of the single magnetic pole head is made equal to the track width has been proposed and this method has attracted public attention as a recording system which well utilizes the high-density recording characteristic of the perpendicular magnetic recording (for example, see IEEE Transactions On Magnetics, vol. 30, No. 6, November, 1994, pp3900-3902).
In this method, information is written by using a plurality of recording single magnetic pole heads that are aligned in a direction parallel to the track direction of a magnetic medium, and information is read out by using a plurality of reproducing single magnetic pole heads that are aligned in a direction perpendicular to the track direction. This method makes it possible to carry out a deep sub-micron track recording with a track width of not more than 0.5 .mu.m.
Moreover, also in a tracking servo system and a high-speed accessing system for such high-density tracks, a track following technique with higher precision which exceeds the conventional servo performances is required. For this reason, in a separate manner from the above-mentioned recording single magnetic pole head, a reproducing single magnetic pole head is installed and its main magnetic pole is aligned so as to make the length direction perpendicular to the tracks; thus, the head is designed so as to have a wider width in the track traversing direction so that a multi-track reproducing is carried out. Here, the tracking is performed based upon the above-mentioned reproducing single magnetic pole head so as to meet the high-speed reproducing process and track following process.
However, in the above-mentioned conventional apparatus, the reproducing process is carried out by using one single magnetic pole head in a manner so as to extend over a plurality of tracks; consequently, pieces of information on a plurality of tracks are simultaneously reproduced, with the result that crosstalk tends to occur. For this reason, an advanced multivalued signal processing circuit, etc., which is completely different from that of the conventional magnetic recording signal process, is required in a separate manner. The resulting problem is that an extremely complex magnetic recording-reproduction apparatus is required.
Moreover, in the conventional apparatus having a reproducing single magnetic pole head in a separate manner from the recording single magnetic pole head, a magnetic head, which has two heads, that is, a recording single magnetic pole head and a recording single magnetic pole head, in a hybrid manner, has to be installed. The resulting problem is that a complicated head manufacturing process is required.